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Heated Glass Element: Description and Operation

How the Circuit Works

Rear Window Defogger

Battery voltage is supplied at all times to the rear window defogger relay contacts through fuse 10 (in the rear fuse/relay box). With the ignition switch in ON (II), battery voltage is supplied to the rear window defogger relay coil and to the climate control unit through fuse 30 (in the under-dash fuse/relay box).

When the rear window/power mirror defoggers switch (in the climate control unit) is pressed, the defog signal is sent to the MICU. The MICU provides ground to the rear window defogger relay coil, energizing the relay. Battery voltage is supplied to the rear window defogger through the energized relay.

The rear window defogger is turned off by pressing the rear window/power mirror defoggers switch a second time of by turning the ignition switch to LOCK (0).

Power Mirror Defoggers

Battery voltage is supplied at all times to the driver's MPCS unit and the front passenger's MPCS unit through fuse 7 (in the under-dash fuse/relay box). With the ignition switch in ON (II), battery voltage is supplied to the climate control unit through fuse 30 (in the under-dash fuse/relay box).

When the rear window/power mirror defoggers switch (in the climate control unit) is pressed, the defog signal is sent to the driver's MPCS unit via B-CAN and then to the front passenger's MPCS unit via UART. The driver's MPCS unit supplies battery voltage to the left power mirror defogger and the front passenger's MPCS unit supplies battery voltage to the right power mirror defogger.

The power mirror defoggers are turned off by pressing the rear window/power mirror defoggers switch a second time or by turning the ignition switch to LOCK (0).